code: def add_case(self, case_name, item):
      self.data[case_name] = item
      self.cases.append(case_name)
  
file_path: DeepNeuro/deepneuro/data/data_group.py
imports: import numpy
  from deepneuro.utilities.conversion import read_image_files
label_desc: Use image node_id 2 for calling the DataGroup obj's underlying member method code with example usage: obj.add_case(case_name, item) without return types